Brokeneck Bikes

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Recumbentist
Recumbentist's picture
Brokeneck Bikes

To avoid shitting up other threads I'm going to post my recumbent bullshit here. I expect that as Tarck ages more of you will be joining me here. I just got here 2 or 3 decades early thanks to my neck.

So I think this is what I'm going to do. This is a rather extravagant build but worth it to me. Rob English is going to be helping me with this.

18-lb Fujin SL II

Fujin SL II, disc
Replace fork with Burroughs 20" monoblade fork

26" ENVE XC race laced to an Alchemy Orc, bladed spokes
32 mm Compass 26" Elk Pass rear tire
Lightening 160 mm crank (haven't decided on gearing yet)
Shimano Di2 XTR
Terracycle Idler kit, ceramic
Some kind of china carbon 406 rim (if anyone has suggestions let me know); Schwalbe One 28 mm tire; probably a SON hub and Edelux.

I would LOVE to ultimately make this dual 26". I saw a very old post from someone where they attempted this, but there wasn't any real feedback on handling. Also concerned about hard interference with the crank. I can accomplish this with a 26" monoblade from BikeFix, but it is a lot of trouble if it isn't going to work. The only thing that makes me anxious about doing 26" is that it makes me completely dependent on Compass 32 mm tires--the other options for relatively narrow 26" are pretty shitty.

Calculated weight from my giant spreadsheet ~16.6 lbs complete with pedals. +/- 0.2 lbs because I don't know if I need a medium or large CF seat.

Wed, 11/23/2016 - 10:45
Todd
Todd's picture

yeah, but dont you need to put a big old flat on a stick on it?

Wed, 11/23/2016 - 11:01
Wilhelm
Wilhelm's picture

I wonder how much (if?) the geometry would change with a 26" front? It looks like the 26" fork compensates for most of the difference in wheel size, but...

Also, do you have to go 26", or can you use 650? That would affect your tire choices, for sure

Wed, 11/23/2016 - 11:13
Recumbentist
Recumbentist's picture

650C would work (in fact that is what is on the spencer shown), but the tire choices are absolutely awful; I'm not riding around on a rock-hard 23 mm tire on my roads.

Wed, 11/23/2016 - 11:28
fixed
fixed's picture

that's amazing you can get it down to 16.6lbs with what must be five pounds of chain on there

recommendation: save the weight of a chain and simply add a battery!

OR save the weight of a battery and add a gas motor!

Wed, 11/23/2016 - 11:29
JUGE FREDD
JUGE FREDD's picture

in real life that 26" Compass '32' is a true 28mm tire

there's fatter and faster 700c tires, I'd think about sticking with that on an aero rim (or doing 650b)

don't know if the XTR Di2 pusher will work with big chainrings, but there's no problem using the MTB buttons with front+rear road gorillas

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Wed, 11/23/2016 - 13:17
Recumbentist
Recumbentist's picture

700C won't fit. That would be the best solution, of course. Not sure if 650B would work, I assume not.

Wed, 11/23/2016 - 13:26
Wilhelm
Wilhelm's picture
(Reply to #7)

Recumbentist wrote:
650C would work (in fact that is what is on the spencer shown), but the tire choices are absolutely awful; I'm not riding around on a rock-hard 23 mm tire on my roads.

Good point...

Wed, 11/23/2016 - 13:42
that guy
that guy's picture

I have no idea what's going on here, but I suspect it's going to be awesome.

Bikes suck. Don't ride one.

Wed, 11/23/2016 - 14:24
Recumbentist
Recumbentist's picture

Dumb question: Stan's Podium MMX rims say 15-33 PSI with a 2" tire. So with a narrower tire is it safe to go higher? Or is it the other way around. Or is it just going to assplode at 70 psi.

Wed, 11/23/2016 - 14:27
johnasavoia
johnasavoia's picture

I have nothing to add except this is all absolutely fascinating and I wish you the best of riding and the least pain while doing so.

Wed, 11/23/2016 - 19:27
turpencat
turpencat's picture
(Reply to #11)

Recumbentist wrote:
Dumb question: Stan's Podium MMX rims say 15-33 PSI with a 2" tire. So with a narrower tire is it safe to go higher? Or is it the other way around. Or is it just going to assplode at 70 psi.

thinner tires are usually rated to higher psi now I don't know if it's because the volume changes are different at that size so you go higher to prevent road manipulation or because the tires have to be higher pressure so they make them that way.

johnnyraja wrote:
If you've never done it then yes, it's very surprising.

Wed, 11/23/2016 - 20:27
jimmythefly
jimmythefly's picture

It has to do with the internal pressure pushing outward on the sidewall and exploding the rim. A larger tire pushes in a different direction and I believe that is the reason you can go higher psi on a narrower tire.

deadforkinglast wrote:
But honestly, I have no idea how I am going to follow through on that plan and I already have a pretty rad spencer. I think I just like fucking with my bikes.

Wed, 11/23/2016 - 23:32
jimmythefly
jimmythefly's picture

Why not go for a more typical 26" wheeled high racer? Heavier? Prefer to be closer to the ground?

deadforkinglast wrote:
But honestly, I have no idea how I am going to follow through on that plan and I already have a pretty rad spencer. I think I just like fucking with my bikes.

Wed, 11/23/2016 - 23:34
DDYTDY
DDYTDY's picture
(Reply to #14)

jimmythefly wrote:
It has to do with the internal pressure pushing outward on the sidewall and exploding the rim. A larger tire pushes in a different direction and I believe that is the reason you can go higher psi on a narrower tire.

Bigger tire = more square inches of force me thinks.. Seems the bigger the tire the bigger the load at the same pressure. I think?

Stoked about this thread.

Thu, 11/24/2016 - 16:48
Recumbentist
Recumbentist's picture
(Reply to #15)

jimmythefly wrote:
Why not go for a more typical 26" wheeled high racer? Heavier? Prefer to be closer to the ground?

I do prefer to be a little closer to the ground, falling off a highracer (and believe me, there's a lot of falling off recumbents when you are learning) is not appealing to me with a neck issue. Although I learned to ride a recumbent on a true scary bastard--the M5 Carbon High Racer, it's been 5 years since I rode one and I'm sure I'm going to be doing a lot of falling off and riding into the bushes again.

I can't believe I rode a lowracer in downtown Manhattan traffic routinely!

Then again, I haven't laid down cash money yet, and this babby came up for sale:

This is a 700C highracer but designed to have the seat as low to the ground as possible. Virtually impossible to get in the US, I didn't even consider it previously. I'd want just the frame/fork/tiller/seat/idlers, as I don't want to set it up like the seller has it.

Thu, 11/24/2016 - 17:04
Recumbentist
Recumbentist's picture
(Reply to #16)

Recumbentist wrote:
jimmythefly wrote:
Why not go for a more typical 26" wheeled high racer? Heavier? Prefer to be closer to the ground?

I do prefer to be a little closer to the ground, falling off a highracer (and believe me, there's a lot of falling off recumbents when you are learning) is not appealing to me with a neck issue. Although I learned to ride a recumbent on a true scary bastard--the M5 Carbon High Racer, it's been 5 years since I rode one and I'm sure I'm going to be doing a lot of falling off and riding into the bushes again.

I can't believe I rode a lowracer in downtown Manhattan traffic routinely!

Then again, I haven't laid down cash money yet, and this babby came up for sale:

This is a 700C highracer but designed to have the seat as low to the ground as possible. Virtually impossible to get in the US, I didn't even consider it previously. I'd want just the frame/fork/tiller/seat/idlers, as I don't want to set it up like the seller has it.

I know recumbents are dorky but I wouldn't be even remotely embarrassed to ride this one.

Thu, 11/24/2016 - 17:05
DDYTDY
DDYTDY's picture

#dorklyfe

Thu, 11/24/2016 - 17:18
jawn doe
jawn doe's picture

how do you feel about under seat steering? my recumbodad prefers it when available- i've never tried it but i do like the way the stoker bars feel on his barcroft tandumb. i always feel like they look more sportier.

i don't have a pic of his but he gets bonus points for his engin-built elevated boom. he's also getting this thing made for a different spencer (i think he has 2 recumbent tandems, 4 single recumbos, one recumbo trike and one viewpoint knockoff)

probably the only dude drew will make brokeneck spencer parts for

Fri, 11/25/2016 - 19:37
Recumbentist
Recumbentist's picture

Can I hang out with your dad?

USS is pretty fun, but I like ASS better. Particularly tillers--much more aerodynamic position.

Rode my trike up Peekamoose Rd in the Catskills yesterday. Max grade 15.3%, I was going like 2 mph. I am worried that I'm not going to be able to make it up that on a 2-wheeled recumbent. Climb followed by 14 miles or so of 30 mph+ riding. Route: https://ridewithgps.com/routes/2413458

Also I've made the decision to sell all my upright bikes--two Englishes, the Herse, and a GT Grade. I just have to accept the fact that I'm not going to ride them again, and that they make my neck worse rather than better.

I have to sell them because it is actively depressing to look at them every day. 9 years of obsessive cycling down the tubes, and my fitness and skills from those 50k miles+ doesn't even really apply to recumbents. Kinda bummed today.

I guess on the plus side recumbents are generally poorly optimized, poorly thought out junk--even the high-end ones--so there will be plenty to keep me occupied.

Sat, 11/26/2016 - 10:18
JUGE FREDD
JUGE FREDD's picture
(Reply to #20)

Recumbentist wrote:
Dumb question: Stan's Podium MMX rims say 15-33 PSI with a 2" tire. So with a narrower tire is it safe to go higher?

It is but you should avoid the fuck out of any older Stan's product, especially the ultra weenie stuff. They set those limits because the rims are flimsy as fuuuck. Even their more substantial ZTR355 was trivial to dent and could barely take 100kgf tension.

Something like this would be way stronger/stiffer/lighter: http://www.nextie.net/mountain-clincher-24mm-NXT26XC24

That would let you drop down to 24 spokes, and use a stouter aero option like the DT Aero Comp

They also make aero rims for 406 and 451: http://www.nextie.net/bmx-20-inch-406-NXT406BMX23

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Sun, 11/27/2016 - 20:51
Recumbentist
Recumbentist's picture
(Reply to #21)

JUGE FREDD wrote:
Recumbentist wrote:
Dumb question: Stan's Podium MMX rims say 15-33 PSI with a 2" tire. So with a narrower tire is it safe to go higher?

It is but you should avoid the fuck out of any older Stan's product, especially the ultra weenie stuff. They set those limits because the rims are flimsy as fuuuck. Even their more substantial ZTR355 was trivial to dent and could barely take 100kgf tension.

Something like this would be way stronger/stiffer/lighter: http://www.nextie.net/mountain-clincher-24mm-NXT26XC24

That would let you drop down to 24 spokes, and use a stouter aero option like the DT Aero Comp

They also make aero rims for 406 and 451: http://www.nextie.net/bmx-20-inch-406-NXT406BMX23

But would it be able to handle an 80psi 32 mm tire? Says 45 psi.

Mon, 11/28/2016 - 00:04
Blakey
Blakey's picture
(Reply to #22)

Recumbentist wrote:
But would it be able to handle an 80psi 32 mm tire? Says 45 psi.

I would bet that 45psi recommended limit is at the widest tyre they spec (1.95"), shoot them an email for max at 32mm, it should go up dramatically.

Eg: DT Swiss rims, moving from 1.95" to 32mm tyres, their max pressure goes from 64 to 99psi
https://www.dtswiss.com/Resources/Tech-PDF/Tire_Pressure_Dimension

It's a bummer that you can't ride 'wedgies' anymore, especially the rad ones you have, but it's rad that you have what will no doubt be a few incredible recumbents in a year or so and still be riding. Especially if Rob is involved.

Mon, 11/28/2016 - 00:58
Recumbentist
Recumbentist's picture

Thanks! I'm going to e-mail them. Now if only someone made a deep 26" carbon road rim. Unfortunately completely nonexistent for obvious reasons.

It's actually going to be a lot less than a year, looks like a February delivery so I can ride around for hours in the freezing cold in figure 8s in a parking lot until I don't crash into things. Also my friend, who is president of the UMCA, is dropping off a Cruz spencer tonight for me to borrow for a few months. Front-wheel drive "moving bottom bracket" just to make things even harder and weirder. This is the spencer all the UMCA crazies use to set 12- and 24-hour records, and the one that Maria Parker wins RAAM on.

Does anyone build custom carbon forks? I want a 20" carbon monoblade with a disc attachment.

Building a recumbent is kind of fun, so many challenges and so many things that can be improved. At least it keeps me occupied.

Oh yeah, I appear to be somewhat faster on my trike than on my diamond frame, but not for a really logical reason. I seem to attack hills really hard because I'm so paranoid about making it to the top. So instead of coasting down one hill and powering up to the top because I know I can make it easily, I sprint down hills as hard as I can and blast up to the top of the next on the trike. I was a little weirded out when I did my quick afterwork 22 miles in less than an hour. That's really fast for me.

Mon, 11/28/2016 - 09:43
capn_pants
capn_pants's picture

Hey, brightside: if you get sick of your job, you have a future with DHL.

Wanna hold hands?

Mon, 11/28/2016 - 11:18
fixed
fixed's picture

are you gonna get a fairing for this thing? that might actually be really awesome for winter cycling. toasty warm!

Wed, 11/30/2016 - 10:03
Recumbentist
Recumbentist's picture

No, no fairing. I also shaved off my incipient beard to avoid stereotypes.

I have an assload of cash from spencer sales, so it is being directly converted into this:

and this:

Wed, 11/30/2016 - 14:27
fixed
fixed's picture

wtf is that little straw for the return chain?
also, for real, why no fairing? it would be like a bar mitt for your body.

Mon, 12/05/2016 - 14:21
jimmythefly
jimmythefly's picture
(Reply to #28)

Recumbentist wrote:
this:

Unf that looks sw8.
Staying 700c or converting to 650b or ?

deadforkinglast wrote:
But honestly, I have no idea how I am going to follow through on that plan and I already have a pretty rad spencer. I think I just like fucking with my bikes.

Mon, 12/05/2016 - 18:25
Recumbentist
Recumbentist's picture

Keeping it 700c. It is a very low highracer so it should be okay. Rob is going to help me e tap it or di2 xtr

Thinking about a truly extravagant wheel set. Like a zipp disc in back and one of those zip nsw 454s in front. Since I'm converting 5 upright spencer proceeds into two bents I can do whatever I want.

I have to admit bents are kind of fun to think about at least. So many custom things I can do that genuinely enhance performance, particularly aerodynamics.

Also working toward a carbon fiber tail box. A good sized one can add several mph at high speeds.

Tue, 12/06/2016 - 01:12
Recumbentist
Recumbentist's picture
(Reply to #30)

fix wrote:
wtf is that little straw for the return chain?
also, for real, why no fairing? it would be like a bar mitt for your body.

The straw is a chain tube. I'm gonna do an over/under idler instead.

I think fairings are okay if you want to say ride it to work as a car replacement. I think rob e had a faired trike for that. But I want to actually enjoy my rides.

Tue, 12/06/2016 - 01:16
ergott
ergott's picture
(Reply to #31)

Recumbentist wrote:
Does anyone build custom carbon forks? I want a 20" carbon monoblade with a disc attachment.

Appleman?

If someone on here did it, I'd probably like it. Since it was done by someone I don't know, they're a fucking idiot.

Tue, 12/06/2016 - 05:15
Recumbentist
Recumbentist's picture

Just checked Appleman--pretty sure that he doesn't build forks.

My research suggests that there are no "custom" CF forks. Makes sense since it is a high-stress high-risk component.

Tue, 12/06/2016 - 08:37
newellbt
(Reply to #33)

Recumbentist wrote:
Just checked Appleman--pretty sure that he doesn't build forks.

My research suggests that there are no "custom" CF forks. Makes sense since it is a high-stress high-risk component.

Wound Up?

Tue, 12/06/2016 - 10:00
NOVELTYNAME
NOVELTYNAME's picture
(Reply to #34)

newellbt wrote:
Wound Up?

not gonna make a single blade one

"Folks want options!"

Tue, 12/06/2016 - 12:52
JUGE FREDD
JUGE FREDD's picture

only real avenue for that would be to do it lefty-style

these guys could prob do one short enough, but their clamps are gonna be for the cannondale 1.5625" steerer

http://www.flatlandbicycles.com/epages/78615894.sf/en_GB/?ObjectPath=/Shops/78615894/Products/25%5B1%5D

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Tue, 12/06/2016 - 17:22
Recumbentist
Recumbentist's picture

Yeah I don't think that would be feasible.

Tue, 12/06/2016 - 18:38
NOVELTYNAME
NOVELTYNAME's picture

if rob english is making the spencer wouldnt he be able to make something super sw8?

"Folks want options!"

Tue, 12/06/2016 - 18:39
Recumbentist
Recumbentist's picture

Actually yes, we already discussed making a monoblade fork. I've just been searching for something in carbon and already made. Trying hard to get <16 lbs.

Wed, 12/07/2016 - 09:27
dorth
dorth's picture

There are crabon 20" bmx forks out there (for race bikes) dual bladed, a bit heavy tho

https://www.danscomp.com/shop-RACE/sg3/BMX+Racing+Forks.html

Thu, 12/08/2016 - 08:01
Recumbentist
Recumbentist's picture

I think at that point I'd just go with a steel fork. M5 used to make a monoblade crabon fork, unfortunately they no longer sell it.

Thu, 12/08/2016 - 09:26
Face
Face's picture

Excuse my ignorance, but why monoblade?

Mr. Pubes wrote:
i fear that you are so lost in your own asshole that you may never be found again. do you have a flare gun? send for help.

Sat, 12/10/2016 - 16:06
oogens
oogens's picture

assuming for marginal aerodynamic benefit?

Sat, 12/10/2016 - 17:12
Endpoint
Endpoint's picture
(Reply to #43)

Recumbentist wrote:
But would it be able to handle an 80psi 32 mm tire? Says 45 psi.

No. Even the Crest had issues with this. The rim compresses so much at higher pressure that the spoke tension required to keep it from coming apart will result in cracking at the nipples in a short amount of time.

Backing Fred on this.

Sat, 12/10/2016 - 23:24
Recumbentist
Recumbentist's picture
(Reply to #44)

Face wrote:
Excuse my ignorance, but why monoblade?

I want to run a dropped chain for efficiency. So I need to either use an offset fork, a fork with very narrow blades, or a mono blade.

Sun, 12/11/2016 - 00:08
Face
Face's picture

That's crazy.

Mr. Pubes wrote:
i fear that you are so lost in your own asshole that you may never be found again. do you have a flare gun? send for help.

Sun, 12/11/2016 - 01:13
Patch
Patch's picture

Why in god’s name would you run 80 psi on a 32? Currently running 35/55 on mine.

Sun, 12/11/2016 - 04:02
JUGE FREDD
JUGE FREDD's picture
(Reply to #47)

Patch wrote:
Why in god’s name would you run 80 psi on a 32? Currently running 35/55 on mine.

a 406mm tire has 60% the volume of a 622mm tire

and the rear of a recumbernt has mega weight distro on it

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Sun, 12/11/2016 - 07:31
jeffro
jeffro's picture

That right there is the kind of knowledge that keeps me coming back.

Sun, 12/11/2016 - 07:34
eric_ssucks
eric_ssucks's picture
(Reply to #49)

JUGE FREDD wrote:
Patch wrote:
Why in god’s name would you run 80 psi on a 32? Currently running 35/55 on mine.

a 406mm tire has 60% the volume of a 622mm tire

and the rear of a recumbernt has mega weight distro on it

#recumbentproblems

Sun, 12/11/2016 - 10:59
emor
emor's picture

In my case I run 70-80 on my 700c 32mm tire because I'm fat

"my main life goal is to have a dirtbag camper van with a bunch of bikes on it, go camping every vacation forever" -- me

Sun, 12/11/2016 - 12:04

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